6
4
Table 6
Acknowledgements
The recyclability of the Fe3O4@SiO2@C22–Pd(II) catalyst in the Suzuki–Miyaura and
the S-arylation reactions.a
This work was supported by the Research Council of the K.N.
Toosi University of Technology. The authors express their gratitude
to Dr. Sogand Noroozizadeh for editing the English content of this
manuscript.
Entry
Cycle
Suzuki–Miyaura yield (%)b
1
2
3
4
5
1
2
3
4
5
84
84
82
78
75
90
90
90
88
85
Appendix A. Supplementary data
a
Reaction conditions were the same as those of Table 2, entry 5 for the
Suzuki–Miyaura reaction, and Table 4, entry 5 for the S-arylation reaction.
found, in the online version, at http://dx.doi.org/10.1016/j.molcata.
b
Isolated yields.
2
015.03.002.
as follows: iodobenzene > bromobenzene > chlorobenzene (Table 4,
entries 1, 5, and 17).
The proposed catalytic cycle for the cross-coupling reaction of
aryl halides and thiols is depicted in Scheme 3. Initially, potassium
hydroxide facilitates the reduction of our Pd(II) precatalyst to Pd(0)
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(
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7
(
acterized
nanoparticle-supported palladium(II)-cryptand 22 complex
Fe O @SiO @C22–Pd(II)] catalyst. The activity of the catalyst
a
new heterogeneous silica-coated magnetic
[
[
3
4
2
(
was tested in Suzuki–Miyaura cross-coupling reactions of aryl
halides with arylboronic acids, as well as the S-arylation of thiols.
This method offers several advantages including high yield, short
reaction time, simple work-up procedure, ease of separation, and
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tolerate a wide variety of substitutions in the reagents.
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